This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. Congenital cytomegalovirus (CMV) infection and disease affects over 40,000 infants annually in the United States and is estimated to leave up to 9,000 children with audiologic and neurodevelopmental sequelae. This research is an ongoing, multidisciplinary prospective longitudinal study of CMV infection in mothers and their infants. Two hundred three subjects with virologically confirmed congenital CMV infection, 103 asymptomatic, 62 symptomatic, and 38 uninfected controls now have been enrolled, and are being followed. Mean age at last follow-up is now 5.4 years for symptomatic, 8 years for asymptomatic, and 13 years for control subjects. CT scans have been performed on 60/62 of the symptomatic infants (67% were abnormal), and 90/103 asymptomatics (26% were abnormal). Audiologic assessments have been performed in 60/62 symptomatics (67% have hearing loss), 98/103 asymptomatics (15% have hearing loss). The aims for the next 5 years are to continue careful follow-up to characterize the incidence of hearing loss as to age at onset, unilateral vs. bilateral, severity, fluctuation, and progression, to determine correlation of very high frequency losses and abnormal cochlear emissions studies with hearing loss, and to relate abnormal CT scans to audiologic and developmental outcome. The differences between asymptomatic and symptomatic congenitally infected subjects and uninfected controls will be compared to determine neonatal predictors of outcome at school age and longitudinal follow-up will continue through high school to document late sequelae that may occur during adolescence.